Beegh



(No Model.)

H. VAN HOEVENBERGH.

ELEGTRO MAGNET PO R PRINTING TELEGRAPHS. No. 316,676. Patented Apr. 28,1885.

WITNESSES z w @MI/Z v 63 N PETERS. PhclG-lllhngmplwf. \Vzsllmglmu. D. c.

, UNITED. STATES PATENT OFFICE.

HENRY VAN HOEVENBERGH, OF ELIZABETH, NEW JERSEY, ASSIGNOR TO THEBALTIMORE & OHIO TELEGRAPH COMPANY, OF BALTIMORE, MD.

ELECTRO-MAGNET FOR PRlNTlNG-TELEGRAPHS.

SPECIPICATIQI'I forming part of Letters Fatent No. 316,676, dated April28, 1885.

(X model To all whom, it may concern:

Be it known that I, HENRY VAN Honvnn- BERGH, a-citizenof theUnitedStates, residing in Elizabeth. in the county of Union and State of NewJersey, have invented certain new and useful Improvements in Electrc-Magnets for Printing'lelegraphs, of which the following is aspecification.

My invention-relates to the receiving-instin- 1o ments ofprinting-telegraph systems. It particularly relates to theelectromagnetic devices employed therein.

The main object of my invention is to im prove the form and constructionof electro 1 magnets, especially such as are used in saidprinting-telegraph instruments, in order that the energy of theelectrical-currents which traverse the coils of said magnets may beadvantageously expended in controlling the po sition of the type-wheel,in effecting the impression of the type upon the receiving-sheet, and inmaintaining the instrument in unison .with the transmitter.

The invention consists in constructing elec- 2 tro-magnets withbranching limbs severally equipped with helices arranged to develop fourpoles to each magnet, two of which are ,preferablyemployed in actuatingthe escapement mechanism, the remaining two being employed for actuatingthe impression-producing device or the unison mechanism.

The invention further includes certain details of construction, and aspecific method of operating the unison device.

The exact subject-matter claimed will be hereinafter specificallydesignated.

In the accompanying drawings, Figure l is a front elevation of such partof a printingtelegraph instrument as is necessary to illus 4o trate theinvention; and Fig. 2 is a perspective view of one of theelectro-magnets, the coils of which are shown theoretically.

Referring to these drawings, A represents a type-wheel normally urgedabout its axis in a given direction by means of a weight, XV,

or other equivalent device acting through suitable intermediatemechanism, which may advantageously consist of a gear-wheel, w, andp1n1on 20 The advance movements of the type-wheel are controlled bymeans of an escapement mechanism consisting of the scape-wheel S,mounted upon the type-wheel shaft S, the pivoted anchor A, provided withpallets c and a engaging in the teeth of said scapewheel, 5 5 apolarized armature, B, carried by said pivoted anchor, and vibratingunder the influence of polar changes in the magnets, to be hereinafterdescribed.

M M are two magnetic systems similar to each other in construction. Itwill therefore suffice to describe the magnet M. The core ofthis magnetis composed of two limbs, M M", united by a common yoke-piece, M Eachlimb is made up of three divisions, m m m, branching from acommoncenter. The yokepieee M connects the divisions m with each other.The line-conductor L is wound first about the branches of one limbsuccessively, and then about thebranches ofthe other. The winding (seeFig. 2) is such that a current traveling in one direction will developthe poles respectively represented by the letters N NS S. These poleswill be respectively reversed by a current of opposite direction. Bothmagnetic systems M and M are included in the circuit of the main line L,either in series or in multiple are, as may be desired. The former isthe plan shown in the figures. Thepoles N S of the magnet M confront theSc polarized armature B on one side, while corresponding poles of themagnet M confront it upon the opposite side. The passage of intermittentcurrents of opposite polarity through the line-wire L cause theoscillation of said polarized armature, and thus control the escapementof the typewhecl in a manner which will be understood by those versed inthe art. The poles N S of the magnet N are employed to actuate animpression-producing mechanc ism, which may consist of a printing-lever,

P, fulcrumed atP, and carrying a platen, P

and armature P the latter confronting the poles N S, and normally heldaway from said poles by the action of the spring P: The re- 5 tractileforce of this spring is regulated by turning the screw P. It should beso adjusted as to prevent the actuation of the printing mechanism inresponse to the short intermittent cnrrents which control the escapementof the type-wheel. The printing-lever should respond, however, tocurrents of increased duration, though of the same strength as thosewhich actuate the armature B. As the armature P is not polarized, itwill respond to such increased currents regardless of their polarity.

In order that the printing-lever may be ac tuated by pauses of definitelength only in the alternating currents, suitable retarding mechanismmay be applied in addition to the spring P, which will help to preventthe lever from answering the short alternating currents that effect theescapement of the type-wheel The poles N S of the magnet N are employedin actuating the unison device, which consists of an armature-lever, U,fulcrumed at U and carrying the armature U, and at its extreme end thedetent U", the office of which is to arrest the type -wheel in positionto print blank by engaging with a suitable stop, U, upon saidtype-wl1eel. The armature-lever U is normally held against the poles N Sof the magnet N by virtue of the magnetism developed in said poles bythe passage of the alternating currents. The retractile spring U isaccordingly adjusted by means of the screw U to exert but a feeble pullupon the armature U, and therefore notwithstanding the reversals ofmagnetism it remains against said poles.

As before described, I use alternating currents normally having enoughstrength to operate the printing-lever if prolonged for a sufficienttime. Such strength is, however, greater than that necessary tooscillate the armature B, which is polarized and not opposed by anyspring-power.

To actuate the unison device, I decrease the strength of the alternatingcurrents to a strength which does not actuate the printing device, andwhich continues to operate the escapement device, but which cannotoppose the spring U. The armature-lever U will then be withdrawn, thedetent U will come intothe path of the stop U, and the typewheel will bearrested in position to print blank.

The transmitting apparatus which is to be operated in connection withthese devices forms no part of the subject-matter of this application.It may be of any convenient form adapted to transmit over the circuitthe necessary electrical conditions for actuating the mechanism abovedescribed.

I claim as my invention- 1. The combination, substantially ashereinbefore set forth, of an electro-magnet consisting of a yoke-piece,two main cores united by said yoke-piece, each of said cores having twoarms branching therefrom, an escapement device acted upon by one pair ofsaid arms, and an impression-producing device acted upon by theremaining pair of said arms.

2. The combination, substantially as hereinbefore set forth, with anelectro-magnet con sisting of a main core having branches, andmagnetizing coils respectively surrounding said main core and itsbranches, of an escapement device applied to one or more of saidbranches and a unison device applied to the remaining branch orbranches.

3. The combination, substantially as hereinbefore set forth, of the twocompound electro-magnets developing four sets of poles, the escapementoperated by the joint action of two of said sets, an impressionproducing mechanism actuated by one of the remaining sets, and a unisondevice operated by the action of the other of the remaining sets.

4. The combination, substantially as hereinbefore set forth, of atype-wheel, an escapement device, an arresting device for stopping saidtype-wheel at the unison-point, an electro-magnet, which when traversedby alternating currents of the strength normally employed for actuatingsaid escapement device restrains said arresting device from action, andwhich when traversed by currents of lesser but determined strengthallows said arresting device to act.

5. In a printing-telegraph instrument, the combination, substantially ashereinbefore set forth, of atype-wheel, means for normally advancingsaid type-wheel through the agency of electric currents of a givenstrength, a unison-detent, and means, substantially such as described,operated through the agency of currents of less strength for permittingsaid unison-detent to move into a position to arrest said type-Wheel andfor simultaneously advancing said type-wheel untilit is arrested by thedetent.

In testimony whereof I have hereunto subscribed my name this 31st day ofJuly, A. D. 1883.

HENRY VAN HOEVENBERGH.

\Vitnesses:

DANIEL W. EDGEOOMB, CHARLES A. TERRY.

